Make the window invisible if dumping to stdout

Signed-off-by: David Oberhollenzer <goliath@infraroot.at>

shadermeh.c

@@ -223,26 +223,41 @@ int main(int argc, char **argv)
 		glBindTexture(GL_TEXTURE_2D, fbo_tex);
 		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0,
 			     GL_RGBA, GL_UNSIGNED_BYTE, NULL);
-		glBindTexture(GL_TEXTURE_2D, 0);
 
 		glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 		glFramebufferTexture(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
 				     fbo_tex, 0);
+	} else {
+		window_show(wnd);
 	}
 
 	/******************** drawing loop ********************/
-	while (window_handle_events()) {
+	while (to_stdout || window_handle_events()) {
 		/* render image to FBO */
-		if (to_stdout)
-			glBindFramebuffer(GL_FRAMEBUFFER, fbo);
-
 		clock_gettime(CLOCK_MONOTONIC_RAW, &frame_start);
 		glClear(GL_COLOR_BUFFER_BIT);
 		glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
 
-		if (!to_stdout)
+		if (to_stdout) {
+			glFlush();
+		} else {
 			window_swap_buffers(wnd);
+		}
 
+		/* get image from FBO, dump to stdout */
+		if (to_stdout) {
+			glGetTexImage(GL_TEXTURE_2D, 0, GL_RGBA,
+				      GL_UNSIGNED_BYTE, fb32);
+
+			convert_for_ffmpeg(fb32, fb24, width, height);
+
+			if (write_retry(STDOUT_FILENO, fb24,
+					width * height * 3)) {
+				break;
+			}
+		}
+
+		/* update timers */
 		clock_gettime(CLOCK_MONOTONIC_RAW, &frame_end);
 
 		iFrame += 1;
@@ -252,23 +267,6 @@ int main(int argc, char **argv)
 		glUniform1f(u_iTimeDelta, iTimeDelta);
 		glUniform1f(u_iTime, iTime);
 		glUniform1ui(u_iFrame, iFrame);
-
-		if (to_stdout) {
-			/* get image from FBO */
-			glBindFramebuffer(GL_FRAMEBUFFER, 0);
-			glBindTexture(GL_TEXTURE_2D, fbo_tex);
-			glGetTexImage(GL_TEXTURE_2D, 0, GL_RGBA,
-				      GL_UNSIGNED_BYTE, fb32);
-			glBindTexture(GL_TEXTURE_2D, 0);
-
-			/* convert to 24 bps and dump to stdout */
-			convert_for_ffmpeg(fb32, fb24, width, height);
-
-			if (write_retry(STDOUT_FILENO, fb24,
-					width * height * 3)) {
-				break;
-			}
-		}
 	}
 
 	/******************** cleanup ********************/

shadermeh.h

@@ -36,6 +36,10 @@ void window_set_vsync(window *wnd, int enable);
 
 void window_destroy(window *wnd);
 
+void window_show(window *wnd);
+
+void window_hide(window *wnd);
+
 bool window_handle_events(void);
 
 

window.c

@@ -194,12 +194,9 @@ window *window_create(unsigned int width, unsigned int height,
 	XSaveContext(x11_globals.dpy, this->wnd,
 		     x11_globals.xctx, (XPointer)this);
 
-	/* set the caption and make the window visible */
+	/* set the caption */
 	XStoreName(x11_globals.dpy, this->wnd, caption);
-	XMapWindow(x11_globals.dpy, this->wnd);
+	this->visible = false;
-
-	this->visible = true;
-	x11_globals.vis_wnd_count += 1;
 
 	/* flush any pending requests to the X Server */
 	XFlush(x11_globals.dpy);
@@ -251,6 +248,30 @@ void window_destroy(window *this)
 	free(this);
 }
 
+void window_show(window *this)
+{
+	if (this->visible)
+		return;
+
+	XMapWindow(x11_globals.dpy, this->wnd);
+	XFlush(x11_globals.dpy);
+
+	this->visible = true;
+	x11_globals.vis_wnd_count += 1;
+}
+
+void window_hide(window *this)
+{
+	if (!this->visible)
+		return;
+
+	XUnmapWindow(x11_globals.dpy, this->wnd);
+	XFlush(x11_globals.dpy);
+
+	this->visible = false;
+	x11_globals.vis_wnd_count -= 1;
+}
+
 bool window_handle_events(void)
 {
 	window *wnd;